1. Technical Field
The disclosed embodiments relate to a method for identifying a rated power of a HID lamp.
2. Description of the Related Art
In high intensity discharge (HID) lamps, such as metal halide lamps, high pressure sodium lamps or mercury vapor lamps, a pressurized electric arc, produced by tungsten electrodes on two sides of the HID lamp, passes through the lamp and then light rays are outputted. These lamps are full with the gas and metal. The gas assists in activating the lamp and the metal is heated to the evaporation point to form the plasma state and the light rays are then outputted. The HID lamps have been recently applied to various illumination occasions, such as gyms, warehouses, theaters, roads, parking areas, roadway or the like.
The HID lamp needs an electronic ballast to trigger and keep the internal electric arc. At present, the commercially available HID lamps need the corresponding electronic ballasts according to the rated powers thereof. For example, the 70W HID lamp needs to use the 70W ballast, and the 150W HID lamp needs to use the 150W ballast. If the ballast is incorrectly chosen, the lifetime of the HID lamp is significantly affected. Therefore, the identification of the rated power of the HID lamp becomes important.